The present invention relates generally to a self-monitoring system for a microprocessor system, which checks itself for accuracy during so-called "cold start", especially accuracy of operations at the output port of the microprocessor. More particularly, the invention relates to a cold start self-monitor system in which hard errors at the output ports can be detected by monitoring load signal levels applied to dummy loads.
In the recent years, various microprocessors have become available for controlling and/or operating various automotive devices, such as engines, brake systems, suspension system, etc. When controlling automotive engines, brake systems or suspension systems, each of which are fundamental to the safety and reliability of vehicle driving, microprocessors must be reliable enough to accurately control and/or operate the vehicle devices. All errors must be avoided or at least detected as soon as they occur.
Various self-monitoring systems and fail-safe systems for the microprocessors applied to controlling and/or operating automotive devices have been proposed and developed to ensure accuracy of microprocessor operation and the earliest possible detection of error in the microprocessor.
The present invention is to provide a newly developed self-monitoring system for a microprocessor which can detects hard errors at the output port to verify accurate microprocessor operation.